Thiocyanoacetate derivative of 4-vinylcyclohexene



Patented May 9, 1950 THIO CYANOKC'ETATE DERIVATIVE F I-VINY-LGYCLOHEXEN-E Herbert L. Johnson, Media, and Archibald -P.

Stuart, -Norwood, Pa, assignors to Sun Oil Company, Philadelphia, Pa., a corporation of New No Drawing. Application August 19, 1947', Serial No. 769,540

This. invention. relates to a novel derivative of A-Viny'lcyclohexene and to a novel insecticide. More particularly. it relates 'tofthe preparation of a thiocyanoacetate derived from 4-vinylc'yclo hexene and to they product thus obtained as well asto-its use as an essential active ingredient in an insecticidal composition of matter.

In copending "application Serial No. 636,510, filed December 21, 1945, by Frances J. Bondhus and H. L. Johnson, now abandoned, and continuation-in-part application Serial No. 778,270, filed October 6, 1947, there is described and claimed the product obtained upon esteriflcation of vinylcyclohexene. Specifically there is disclosed and claimed in said continuation-inpart application the chloroacetic acid ester prodnot obtained by adding 4-vi-nylcyclohexene to a solution of monochloroacetic acid, chloroform, andboron trifluoride diethyl ether complex. Another method for preparing the mohochloroacetate consists... in. adding fairly concentrated sulfuric acid to a solution of l-vinylcyclohexene and monochloroacetic acid. In each case heat is required for completion of the reaction. Ex-

amples I, II and III below more fully set out the preparation of the chloroacetic esters.

According to this invention there is provided a novel and useful derivative of -vinylcyclohexene by refluxing the aforesaid chloroacetate derived from 4-vinylcyc1ohexene with one to two moles of sodium thiocyanate employing water and acetone as solvents during the refluxing operation. Example IV more fully sets out this preparation. It is not possible to purify the product of the invention by distillation and for this reason no really significant physical properties can be given. However, it is clear from analysis of the product of the invention given in Example IV that it contains sulfur in an amount quite close to that theoretically expected.

It will be clear to the chemist that modification and variation are possible within the scope of the invention.

Thus, thiocyanates equivalent to sodium thiocyanate in the preparation can be used. In place of water and acetone there may be employed water and ethanol, methanol, dioxane, etc. Other closely related haloesters. of 4-vinylcyclohexene can be used as starting materials in the preparation of the novel product of this invention.

Example I The monochloroacetate derived from 4-vinylcyclohexene was prepared by dissolving 21.3 g. of boron trifluoride-diethyl ether complex in 94.5

'3 Claims. (Cl. 167- 30) '2 grams of monochloroacetic acid and 250 m1. of chloroform. To this mixture "at 50 C. was added dropwise 103 grams of 4-vinylcyclohexene over a period of minutes. The mixture was heated at the same temperature for. an additional three hours and was allowed to stand overnight at room temperature before the reaction mixture was separated. The yield of the inonochloroacetate was 30.6%. The bismonoch-loroacetate of 4-vinylcyclohexene and polymer yield was 25.0% while the unreacted 4 vinylcyclohexene was 36.5%. The monochloroaceta-te of l-vinylcyclohexene was characterized by a boiling range of fi l-5 C. at 0.25 mm. Hg, N 1.4816. The:"'calcuiated chlorine analysis was Cl=17.-50'% while chlorine found in this sample \vasCl='17.71%.

Example II A second procedure was usedfor synthesizing the monochloroac'etate. .To 9.1500 ml. 3 -neck flask fitted with a thermometer, reflux condenser, dropping funnel and mercury sealed stirrer was added 1 mol (130 ml.) of 4-vinylcyclohexene and 1 mol (94.5 g.) of chloroacetic acid. The mixture was heated to C. and 28.2 g. (20 ml.) of 50% sulfuric acid was added dropwise over a period of 17 minutes. The reaction mixture was kept at the same temperature for an additional 11% hours. The product was cooled and diluted with diethyl ether and washed with sodium bicarbonate solution, dried, and distilled. The product consisted of 18.5% of recovered 4-vinylcyclohexene, 16.8% of monochloroacetate, 39.1% of bis-chloroacetate and oily polymer, and 32.4% residue.

Example III acylation takes place without the use of a mineral acid catalyst. Howevenwe have found that better yields are obtained when a small amount of sulfuric acid, BFa-diethyl ether complex, or H2804 and BF3 are used as catalysts.

Example IV A mixture of 226 g. (1.12 mols) of the chloroacetate derived from 4-vinylcyclohexene, B. P.

645 (0.3 mm), 12, 1.4816 121.5 g. (1.5 mole) of sodium thiocyanate, 80 ml. of water and 800 ml. of acetone was refluxed for 16 hours. The reaction mixture was poured into excess water and the organic layer separated. The aqueous layer was extracted with benzene, and the combined organic layer dried. The solvent was removed under vacuum leaving 242.5 g. (89.3%) of the thiocyanoacetate derived from 4-vinylcyclohexene. This material could not be distilled, even under 1 mm. pressure, without decomposition.

Calculated for C11H15NO2S, S, 14.3%. Found, S, 12.8%; CI, 0.1%.

As indicated, the product of the invention has use as an essential active ingredient in an insecticidal composition of matter. Thus, tested against the common housefly by the standard Feet-Grady method the following results were obtained using the crude thiocyanoacetate derivative dissolved, as a 5% by weight solution, in

,Deobase, a deodorized kerosene usually employed .for insecticide sprays:

5% by wt. %by wt. in Deobase in Deobssc Total of tiles (389 mm Average per cent knockdown in 10 minutes 98. 9 96. Q Grate designatlon B AA T. I. difierence +0. 6 +214 Actual kill of O. T. I 63. 8 68.3 Total Kill of sample tested -1 64. 4 95. 7 Knockdown of O. T. I. in 10 minutes. 98. 0 98. 2

of an alkali metal thiocyanate at an elevated temperature in the presence of a solvent, and separating the product from said solvent and any unreacted alkali metal thiocyanate.

2. A novel insecticidal composition comprising a carrier and the thiocyanoacetate derived from 4-vinylcyclohexene by esterifying 4-vinylcyclohexene with monochloroacetic acid, said esterification being effected at an elevated temperature in the presence of an acid type catalyst, reacting the ester product with at least an equivalent quantity of an alkali metal thiocyanate at an elevated temperature in the presence of a solvent, and separating the product from said solvent and any unreacted alkali metal thiocyanate.

3. The thiocyanoacetate derived from 4-vinylcyclohexene by esterifying 4-vinylcyclohexene with monochloroacetic acid, said esterification being effected at an elevated temperature in the presence of an acid type catalyst, reactin the ester product with from 1 to 2 moles of an alkali metal thiocyanate at an elevated temperature in the presence of a solvent, and separating the product from said solvent and any unreacted alkali metal thiocyanate.

HERBERT L. JOHNSON. ARCHIBALD P. STUART.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Haury Aug. 5, 1947 

1. THE THIOCYANOACETATE DERIVED FROM 4-VINYLCYCLOHEXENE BY ESTERIFYING 4-VINYLCYCLOHEXENE WITH MONOCHLORACETIC ACID, SAID ESTERIFICATION BEING EFFECTED AT AN ELEVATED TEMPERATURE IN THE PRESENCE OF AN ACID TYPE CATALYST, REACTING THE ESTER PRODUCT WITH AT LEAST AN EQUIVALENT QUANTITY OF AN ALKALI METAL THIOCYANATE AT AN ELEVATED TEMPERATURE IN THE PRESENCE OF A SOLVENT, AND SEPARATING THE PRODUCT FROM SAID SOLVENT AND ANY UNREACTED ALKALI METAL THIOCYANATE. 